Termination strip for electric cable



Sept. 30, 1958 w, RICHTER 2,854,502 I TERMINATION STRIP FOR ELECTRICCABLE Filed Dec. 5, 1956 INVENTOR. HERMAN W. RICHTER HIS ATTORNEY.

United States Patent -O TERMINATION STRIP FOR ELECTRIC CABLE Herman W.Richter, East Rochester, N. Y., assignor to Tape Cable Corporation,Rochester, N. Y., a corporation of New York Application December 5,1956, Serial No. 626,481

3 Claims. (Cl. 17488) This invention relates to termination devices andmore particularly to devices adapted for use with multiconductor cablesin certain electrical and electronic applications. Such terminationdevices are commonly known as plugs or connectors, and are often furtherclassified as male or female. Pairs of such connectors are usually heldtogether by friction, although positive mechanical locking means arealso sometimes provided. One object of the present invention is toprovide a termination device or connector of the above character havinga more practical and efficient construction and mode of operation.

One of the primary drawbacks of connectors heretofore known and used hasbeen the fact that the connectors often become separated from the cablebecause of careless or rough use. This problem is particularly acutewhere the mating connectors are of the friction gripping type, for insuch instances the connectors are often separated by a pull on the wiresor cable leading to the connector. This method of disconnecting theconnectors often separates part or all of the cable from the connector,thereby placing one or more circuits out of operation. Therefore,another object of my invention is to provide a connector in which thecable is so securely fastened to the connector that any longitudinalforces applied to the cable will be absorbed or passed directly to thebody of the connector and will not cause a rupturing of the connectionsbetween the individual conductors of the cable and the individualconductors on the connector.

It is another object of my invention to provide a connector havingstress absorbing means which are so constructed that connectors whichare held together solely by friction, may be separated by merelyexerting a pull on the cables or wires leading to the connectors.

A further object is to provide a connector of the above nature which maybe made from a one-piece member and which is formed with integral stressabsorbing means, whereby additional clamping members are unnecessary.

A further object is to provide a device having the above advantageswhich may be readily assembled and manufactured by known methods andwith known machinery.

To these and other ends the invention resides in certain improvementsand combinations of parts, all as will be hereinafter more fullydescribed, the novel features being pointed out in the claims at the endof the specification.

In the drawings:

Fig. 1 is a perspective view showing a length of cable attached to aconnector having integral stress absorbing means embodying the presentinvention, and

Fig. 2 is a sectional elevation substantially along the lines 22 in Fig.1.

The preferred embodiment of the present invention, herein disclosed byWay of illustration, is preferably formed from a one-piece blank orboard of dielec- Patented Sept. 30, 1958 tric material, of limitedthickness, as for example, 4 of an inch. Material comprising board 10must have sufficient mechanical strength to withstand normal usage, alow moisture absorption rate and must be capable of withstandingmoderate operating temperatures without softening or decomposition. Ihave found that the blank may be made from epoxy-Fiberglas,silicone-Fiberglas, Teflon-Fiberglas, or alpha cellulose fibersimpregnated with phenolic resin, or other known and suitable materialssuch as those now used in making conventional printed circuit boards.

Connector 10 is preferably formed with a plurality of spaced, metalconductors 11 which are fixed to one or more surfaces thereof in anysuitable manner, as for example, by etching, electroplating, or anyother means now used in the production of the conventional and knownprinted circuits. As shown in Fig. l, conductors 11 extend along theupper surface of the connector from the front edge 12 rearwardly for asuitable distance to provide space for the individual wires orconductors of an electrical cable to be attached thereto, as bysoldering or by other suitable known means. Conductors 11 are preferablypositioned parallel to one another and are so spaced that the conductorsof the cable may be readily aligned therewith for ease in connection.

Although the above connection between the cable and the connectorprovides good electrical conductivity, this connection has limitedmechanical strength and the cable may readily become separated from theconnector, particularly when the cable is used as a handle forseparating the connector from the mating friction type connector. Mycombination connector and stress absorbing device is particularlyadapted to eliminate this problem. I have found that a strong mechanicalconnection may be obtained between the cable connector if the connectoris provided with a pair of spaced, substantially parallel slots oropenings 13 and 14 and the cable is threaded therethrough, as hereaftermore fully described. Slots 13 and 14 cooperate with the remainingportions of the connector, including the rear edge 15 thereof tosecurely fasten the cable to the connector so that the cable andconnector will not separate even when the connector is carelessly pulledout of engagement with a mating connector as by a pull applied to thecable.

My connector is particularly well adapted for use with a ribbon-likecable 16 which is substantially rectangular in cross section, as shownin Fig. l, and which is more fully disclosed and claimed in my copendingapplication, Serial No. 605,628. Cable 16 preferably comprises a pair oftransparent insulating members 17 and 18 having a plurality of spaced,parallel metal conductors 19 laminated therebetween. Each of conductors19 is adapted to be connected to a specific one of fixed conductors 11,as by soldering or other suitable means, as shown in Fig. 1. For thispurpose, insulating members 17 and 18 are preferably stripped back for ashort distance from the free end of the cable, as shown in Fig. 1.

As described above, termination connector 10 is formed with slots 13 and14. These slots preferably extend substantially transversely across theconnector and are located between the rearward edge of fixed conductors11 and the rear edge 15 of the connector. Slots 13 and 14 areexaggerated in width for the purposes of illustration. I have found thatif cable 16 is fed around the rear edge 15 of connector 10 and throughslots 13 and 14, in the following manner, the cable and connector aresecurely connected together. The above connection has sufficientstrength so that the connector and cable remain fastened together underconditions of normal usage, and even when the cable is used as a handlefor disconnecting a pair of mating frictionally engaging connectors.

To this end, cable 16 preferably extends rearwardly from its connectionsto fixed conductors 11 around the rear edge 15 of connector 10, andthence forwardly along the undersurface of the connector and up throughopening 13. Thereafter, cable 16 extends rearwardly along the uppersurface of the connector to opening 14- from whence it extendsdownwardly through said opening to the undersurface of said connector,and thence rearwardly to the rear edge 15 of the connector. The cableextends upwardly along edge 15, thence forwardly along the upper surfaceof the connector and underneath the first described pass of the cable,and thence downwardly through opening 13 from whence it continues forthe desired length for connection to a suitable connector or otherelectrical device. In the present illustration, 1 have shown the cableas extending rearwardly underneath connector 10 toward the right edge ofthe drawing after its last described pass through opening 13, but thisis not necessary, and the cable may extend in any direction afterpassing through opening 13.

As a result of the above construction, cable 16 and termination strip 10are securely bound together, without the use of extra mechanical devicesor separate clamping means. Any pull on the right hand end of cable 16causes the opposing surfaces of the cable to frictionally engage oneanother, as at points or areas 20, 21, 22 and 23. That is, any movementto the right of the right hand end of cable 16 causes the outer layer ofthe cable to move to the right at 20 while the inner portion is causedto move to the left. Similarly, at 21 the forward or outer layer ofcable 16 is being moved downwardly while the inner layer is being movedupwardly. In like manner, at 22 the inner layer of the cable is beingmoved upwardly while the outer layer is being moved downwardly, and at23 the upper or top surface of the cable tends to move to the rightwhile the under layer tends to move to the left. Thus, my device causesthe adjacent layers of the cable to move in opposite directions throughout a considerable distance whereby a high degree of frictionalresistance is set up between the layers. This frictional resistanceresists any action tending to separate the cable from the terminationstrip and provides a high degree of mechanical strength.

Thus, it will be seen that my invention accomplishes its stated objectsand provides a combination termination strip or connector and strainrelieving device whereby a multi-conductor cable may be connected to aseries of fixed, spaced conductors and whereby the cable is preventedfrom being accidentally separated from the termination strip. My deviceprovides :a mechanical connection having such strength that theconnector may be readily disconnected from its mating device by simplyexerting a quick sharp pull on cable 16. Since this is the common methodfor disconnecting some devices, my strain relieving construction insuresthat such use will not damage the electrical connections between thecable and the connector.

It will be understood that while I have shown all of fixed conductors 11as being positioned on the upper surface of strip 10, part of theconductors may be placed on the undersurface of the strip and the cableseparated at a point adjacent opening 13 and part fed through saidopening for connection to conductors on the underside of the strip whilethe remaining portion of the cable is connected to the conductors on theupper side of the strip. Similarly, while I have shown the terminationdevice as being substantially rectangular, it may be square, round orhave any other suitable shape.

It will thus be seen that the invention accomplishes its objects andwhile it has been herein disclosed by reference to the details of apreferred embodiment, it is to be understood that such disclosure isintended in an illustrative, rather than a limiting sense, as it iscontemplated that various modifications in the construction andarrangement of the parts will readily occur to those skilled in the art,within the spirit of the invention and the scope of the appended claims.

I claim:

1. The combination comprising a multi-conductor cable and a terminationstrip, a plurality of fixed conductors on said strip extending along onesurface thereof, said strip being formed with a plurality ofsubstantially parallel spaced openings said cable being connected at oneend thereof to said fixed conductors and extending rearwardly above saidfirst mentioned surface of said termination strip over the rear edgethereof and forwardly below the opposite surface of said terminationstrip and thence through said opening nearer said fixed conductors andalong said first mentioned surface of said termination strip and thencethrough the other of said openings and along said opposite surface ofsaid strip around the rear edge of said strip underneath said earlierdescribed pass of said cable and thence forwardly above said firstmentioned surface of said strip and beneath said first described pass ofsaid cable, and thence through said nearer opening.

2. The combination comprising a multi-conductor cable and a terminationstrip, a plurality of fixed conductors on said strip extending along onesurface thereof, said strip being formed with a plurality ofsubstantially parallel spaced openings extending substantiallytransversely to the longitudinal axis of said fixed conductors saidcable being connected at one end thereof to said fixed conductors andextending rearwardly above said first mentioned surface of saidtermination strip over the rear edge thereof and forwardly below theopposite surface of said termination strip and thence through saidopening nearer said fixed conductors and along said first mentionedsurface of said termination strip and thence through the other of saidopenings and along said opposite surface of said strip around the rearedge of said strip underneath said earlier described pass of said cableand thence forwardly above said first mentioned surface of said stripand beneath said first described pass of said cable, and thence throughsaid nearer opening.

3. The combination of a multi-conductor cable and a termination strip,said strip having a plurality of fixed conductors along one surfaceextending rearwardly from the front edge thereof, said strip beingformed with a pair of substantially parallel spaced openings between therearward edge of said fixed conductors and the rear edge of saidtermination strip, said cable being connected at one end thereof to saidfixed conductors and extending rearwardly above said first mentionedsurface of said termination strip over the rear edge thereof andforwardly below the opposite surface of said termination strip andthence through said opening nearer said fixed conductors and along saidfirst mentioned surface of said termination strip and thence through theother of said openings and along said opposite surface of said striparound the rear edge of said strip underneath said earlier describedpass of said cable and thence forwardly above said first mentionedsurface of said strip and beneath said first described pass of saidcable, and thence through said nearer opening.

References Cited in the file of this patent UNITED STATES PATENTS2,658,983 Talbot Nov. 10, 1953

